The present invention relates to structures employed in double belt presses for simultaneously tensioning and controlling the stationary and rotating belts.
In double belt presses operating according to the rolling bed principle, a compression force is generated in a reaction zone between rotating belts which are driven externally via their edges. The belts are supported by a stationary supporting structure via a succession of roller bearings from a roller bed for each belt. The forces generated in the reaction zone as well as the driving or friction forces are transmitted to the supporting structure through each roller bed. This state of the art is disclosed in my U.S. Application Ser. No. 114,673, filed Jan. 23, 1980 for CONTINUOUS LAMINATING MACHINE and corresponding to German Application No. P 27 37 629.0 of Aug. 20, 1977.
The solution disclosed in those applications for tensioning presents certain drawbacks in that it is not as economical as it could be, and is not suitable for influencing, i.e., controlling, the direction of movement of the belts through the reaction zone. However, such control is necessary if specific, high pressures are to be established in the reaction zone of the double belt press or if, for example, flaws occur in the geometric configuration of the supporting structure as a result of deformations.